Sn-4.8Bi-0.7Cu无铅焊料的压入蠕变行为  

Indentation Creep Behavior of Sn-4.8Bi-0.7Cu Lead-free Solder

作　　者：曾明[1] 胡丽[1] 张业明[1] 刘新刚[1] 刘家麟[1] 

机构地区：[1]西华大学材料科学与工程学院,四川成都610039

出　　处：《西华大学学报（自然科学版）》2010年第2期69-72,共4页Journal of Xihua University:Natural Science Edition

基　　金：四川省教育厅重点培育项目(07ZZ033);西华大学材料加工工程省级重点学科基金支持

摘　　要：研究了Sn4．8Bi-0．7Cu无铅焊料在温度为40～115℃，应力为10～25MPa条件下的压入蠕变性能，获得了稳态蠕变的本构方程，分析了蠕变前后的显微组织变化，探讨了其蠕变机制。结果表明：Sn-4．8Bi-0．7Cu无铅焊料蠕变中的应力指数n为3．0，蠕变激活能Q为45kJ／mol，材料结构常数A为6．3×10^-9，稳态蠕变本构方程为：ε＇=6．3×10^-9σ^3.0exp（-4．5×10^4／RT）。焊料合金的蠕变量随着温度的升高和应力的增加而加快增大。蠕变前焊料显微组织中有亮块状Bi相、短片状Cu6Sn5金属间化合物；蠕变后Bi相重新固溶到Sn基体，Cu6Sn5金属间化合物弥散分布于基体中，提高了焊料的抗蠕变性能。The indentation creep property of Sn-4.8Bi-0.7 Cu lead-free solder at 40 - 115 ℃ and 10 - 25MPa was tested. The constitutive equation was obtained. Changes of the micro-structure and organization before creep and after creep, and the creep mechanisms were analyzed. The results show that the stress exponent n is 3.0, creep activation energy Q is 45kJ/mol, and the material structure constant A is 6. 3 × 10^-9. The constitutive equation of the indentation creep steady-state creep rate ε＇ = 6. 3 × 10^ -9σ^3.0exp（ -4. 5 × 10^4/RT）. The creep deformation of solder increases accelerately with the increase in temperature andstress. The ashine massive phase Bi and small flake Cu6Sn5 （IMC） are precipitated before creep. The matrix Sn is strengthened by anew dissolving phase Bi and dispersive distribution of Cu6Sn5 （IMC） after creep, which improves the creep resistance of Sn-4. 8Bi-0. 7Cu solder.

关 键 词：Sn-4.8Bi-0.7Cu无铅焊料 压入蠕变 本构方程 显微组织 

分 类 号：TG132.3[一般工业技术—材料科学与工程]